Greenhouse winter cropping

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Elmigo
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Dear Kitchen Garden Lovers,

I need your advice!

Last march I bought Bok Choy from a local farmer. It was grown locally. Knowing Bok Choy doesn't stay good for long, they must have grown it in the winter using a greenhouse with lights and a nice heating and climate system.

What crops can be grown in the winter inside the greenhouse? I'm thinking cauliflower or some other nice crops. Do I need a heating system or can it be done only using the greenhouse itself? Which other crops can be grown in winter?
Monika
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Elmigo, there was quite a discussion on this topic not so long ago and somebody cleverer than I will no doubt point you to this link in the archive, but I have certainly always found that the lack of light determines what to grow rather than the lack of heat. To me, even winter lettuce which its frost hardy always seems much tougher than succulent summer lettuce. But that might just be because we live further north and also higher up than many of the contributors to this forum.
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Primrose
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I think the answer is thst it,s going to be a struggle because as Monika says, light levels are so low. I would try Swiss chard. Giant Fordhook is a particularly robust variety and when small can be used as a salad leaf as well than a cooking vegetable like spinach. Winter Density lettuce might be worth a try but you'd need to be sowing these Immediately to give them a start while there,s still enough heat and light for germination. Endive (both flat leaved and frizzy varieties) are a salad I,ve managed to grow under cloches in a border in a mild winter.

As an experiment ive got three Lovely little cabbages growing in an container which uNtil a couple of weeks ago was growing potatoes. I mixed in a lot of grass cuttings with the old compost and planted the cabbage seedlings. I think the decomposition if the grass has generated quite a lot of base heat as they compost down and this has given them a good start. I know you dont have any
grass cuttings but do you have any kitchen waste you could use in a similar way to give your late greenhouse seedlings a bit of a heat boost?
Westi
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I'm unsure of your latitude Elmigo but I sowed Pak Choi in the tunnel beginning of last month & harvested one already (Got a few days of sunshine in the mix I know). Took a chance & sowed some more which are up & sturdy. They just bolt if too hot along with most of the Chinese brassica's so always fail outside in the summer - edible but not pretty. I have a friend with a proper greenhouse (Yep lots of greenhouse envy with her 1/2 bricked number with heating but no lights), who grew the biggest monsters & they were over wintered. If up enough & sturdy they just sit & grow again when opportunity allows even if just a wee window of sunshine then kind of stop again! Lights would definitely help but blows the cost!
Westi
Elmigo
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I'm pretty sure LED growing lights won't blow the cost as much, but it's obvious I need electricity in there for some lighting. Thank you all, I'm going to try a thing or two for this winter :)
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Primrose
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Give it a try Elmigo. There isn't much else gardening activity going on during winter so it makes anything you ARE able to grow doubly valuable, just being able to pop outside and pick your own bit of edible greenery is very satisfying

There,s one thing about the use of artificial lighting I,m uNsure about. Do you use it to intensify the amount of lighting available during a specific period or to lengthen the amount of time available for light exposure? Or both?

Perhaps if you experiment along these lines, or somebody else has some experience of this you will report back and educate us all.

I don,t know whether anybody has gone to the extreme here and had pots of edibles they,ve actually bought Indoors from their greenhouse every evening to take advantage of the extra artificial light available inside the house during the evening hours? Or would this be the wrong king of light if there is such a thing?
Elmigo
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I do know a thing or two about growing lights, as they can be used to completely replace sunlight too. For this you will need some very expensive lighting systems. The cheaper and more affordable lights are perfect for adding light, or extending the light hours a little bit. Last year I used lights for sowing peppers and tomatoes in february when the sun doesn't shine a lot. Grew them in the windowsill and compared to growing without lights, those little seedlings didn't stretch out at all! So it does work for early sowing but as a sun replacement the cheaper ones are insufficient (not strong enough, not the right color temperature or both).

I never knew about the salad crops that were (somewhat) frost hardy! Salad crops usually don't need full sunlight so they might do well in the greenhouse if somehow I can keep the temperatures up, or use hardy salad crops.
sally wright
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https://www.amazon.co.uk/Winter-Harvest ... 606&sr=8-1

I have found this book to be quite informative on winter cropping; for both indoors and out.
Regards Sally Wright
Westi
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Sally, thanks for that link, I've not seen that come up on my searches for more info for what to grow out of season & what I do find is pretty contradictory in some books.

Off to buy now! Cheers again!
Westi
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